Automatic telephony; a comprehensive treatise on automatic and semi-automatic systems (1921)
Smith, Arthur Bessey, b. 1875, Campbell, Wilson Lee · New York : McGraw-Hill · leaf 296
ine, currentflows from the private wiper of theselector through the contacts C-200 tothe center of a bridge coil whose twowindings are indicated by r-2 andr-3. The current thus divides thepasses over both sides of the trunkcircuit to the cord apparatus in themanual office and passing throughthe… … Fig. 236.—Rotary switch.
Telephone
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